Depositphotos
A team of researchers from the School of Engineering at the University of California, Los Angeles, has found a way to extend the life of hydrogen fuel cells.
In particular, the developers presented an innovative design of a pure platinum catalyst and a protective layer of graphene with a porous carbon carrier. The solution based on the protection of platinum material with graphene allowed to extend the service life hydrogen fuel cells to more than 200 thousand hours. This is 8 times higher than the U.S. Department of Energy’s requirement to achieve a service life of 30 thousand hours by 2050 for powerful hydrogen fuel cell systems with a flow membrane.
The development paves the way for the production of relevant hydrogen engines for trucks. Although trucks account for only 5% of total vehicles, they are responsible for almost a quarter of all harmful transport emissions. The use of batteries offers a more environmentally friendly alternative, but their weight and slow charging times are a problem, limiting their use in trucks.
«With a projected power output of 1.08 watts per square centimeter, fuel cells with the new catalyst can deliver the same performance as conventional batteries that weigh eight times more», — the developers say.
Hydrogen fuel cells offer much faster refueling and a more promising alternative. However, the problem was the constant degradation of the catalyst, which limited their widespread use. Conventional platinum alloy catalysts used to accelerate chemical reactions to generate electricity from hydrogen lose efficiency over time as alloying metals leached in aggressive environments.
To solve this problem, American engineers have coated ultra-thin platinum nanoparticles with a protective layer of graphene, which has high strength and conductivity. They then embedded these graphene-coated particles in a porous carbon carrier material called Ketjenblack.
This design made it possible to protect the platinum material from leaching. According to the results of the durability test, which simulated real driving conditions with 90 thousand voltage cycles, the catalyst showed a power loss of less than 1.1%. For comparison, a loss of more than 10% is usually considered excellent. According to the head of the research team, professor of materials science Yu Huang, this level of durability predicts the service life of hydrogen fuel cells to be more than 200 thousand hours.
«Powerful fuel cell systems must withstand harsh environments for long periods of time, so durability is a key concern. This innovation ensures that the catalyst will remain active and reliable even in the harsh conditions typical of long-haul transportation», — said Yu Huang.
The results of the study were published in the journal Nature
Source: Interesting Engineering